Cudjoe Key resident Walt Drabinski filed a lawsuit Thursday and requested an injunction to stop construction on a $150-plus million sewer project in the Lower Keys.

The lawsuit stems from the Florida Keys Aqueduct Authority (FKAA) installing grinder pumps and low-pressure systems in densely populated areas from Sugarloaf Key to Big Pine Key that will be served by the Cudjoe Regional Wastewater System.

Drabinski argued that densely populated areas, such as Cudjoe Key, should be covered by gravity sewer systems, not low-pressure systems and grinder pumps. Gravity sewers do not require electricity or the use of generators, so people have argued they would do better during flooding, tropical storms and hurricanes.

The system the FKAA chose is initially cheaper, but will wind up costing significantly more in maintenance in the long run, says Drabinski, an electrical engineer and CEO of Vantage Energy Consulting.

The current plans call for up to 2,800 of the 8,800 homes to be served by a grinder pump and the low-pressure system. Residents of Cudjoe Gardens, Big Pine Key and Sugarloaf Key would have a combination of gravity and low-pressure systems. Drabinski proposed reducing the number of grinder pumps by two-thirds, and placing them only "where they make sense."

He also contended FKAA sped up the construction schedule to start installing the low-pressure systems and grinder pumps in his neighborhood before he could legally challenge the project designs.

Drabinski said he has lobbied the County Commission, FKAA and Clerk of Court's office to change some of the designs, but that his pleas have fallen on deaf ears. He formed a group called the Sir Isaac Newton Coalition, a play on the gravity concept.

"We believe the facts clearly show that FKAA's analysis is flawed, that the promises made by the county in May 2012 were not kept and that we will be irreparably harmed if an injunction is not granted," Drabinski said.

He spoke last week at a bond hearing before Circuit Court Judge David Audlin, lobbying the judge not to validate the bond for the Cudjoe Regional project.

Drabinski claims the county risks losing $30 million in "State Revolving Loan Funds," because the documents it used to receive the loans -- made available to the public -- downplay the use of grinder pumps and state that gravity systems would be used in densely populated areas.

Audlin is still reviewing the documents and weighing the arguments to determine whether the county and FKAA have violated any of the conditions of the bond to pay for the project.

Florida Keys Aqueduct Authority Executive Director Kirk Zuelch argued that detailed plans dating back to 2009 show the use of low-pressure systems in some densely populated areas.

"This was designed to be a hybrid system that would include the use of gravity, low-pressure, grinder pumps and on-site systems," Zuelch said. "This is most efficient and cost-effective system. It's a difficult region to serve because it is spread out over multiple islands. It's a good system that saved millions of dollars for our community."